High-tension oil-switch.



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APPLICATION FILED FEB. 25, 1902.

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INVENTOR vl/ ATTOZNEY WITNESSES. 7e .01 wflz Patented. May 24., 1904.

UNITED STATES PATENT OFFICE.

HENRY PRICE BALL, OF NEW YORK, N. Y., ASSIGNOR TO GENERAL INOANDESOENTARC LIGHT COMPANY, OF NEVV YORK, A OORPO- RATION.

HIGH-TENSION OIL-SWITCH.

SPECIFICATION forming part of Letters Patent No. 760,601, dated May 24,1904.

Application filed February 25, 1902. Serial No. 95,609. (No model.)

To all whom it may concern.-

Be it known that I, HENRY PRICE BALL, a citizen of the United States,residing at New York city, county and State of New York, have inventedcertain new and useful Improvements in High-Tension Oil-Switches, ofwhich the following is a specification.

My invention relates to oil-switches of the type especiallydesigned foruse with circuits transmitting high-tension large-quantitycurrents*such, for instance, as a six-thousandvolt three-phase current.

My invention consists in the construction of the switch and in the meansfor electrically operating the switch from a distance.

The general object of my invention may be stated to be the constructionof a switch for safely handling high-tension large-quantity currents andwhich under ordinary conditions of service will not be injuriouslyaffected by the are produced upon breaking the circuit or if injured byan excess of arc may be readily and quickly repaired.

A further-object of my-invention is to provide mechanism for operatingthe switch, which may be energized through the instrumentality of simpleelectromechanical means located at a distance.

The accompanying drawings will serve to illustrate my invention, and inwhich similar letters and numerals indicate like parts.

Figures 1, 2, and 3, are diagrams illustrating the circuit connectionsbetween the mechanism for operating my improved oil-switch andelectromechanical means for energizing the operating mechanism and alsoshowing the successive positions of the parts. Fig. 4 is a frontelevation of the oil-switch and its actuating mechanism. Fig. 5 is aside elevation taken on the line X X of Fig. 4. Fig. 6 is a verticalsection through one of the magnets of the actuating mechanism and itsdashpot. Fig. 7 is a longitudinal section through the left-hand upperjoint of the movable support for the oil-wells. Fig. 8 is a verticalsection through one of the oil-wells with one of the bridge-rods in aclosed position. Fig. 9 is avertical section through the guide, cap, andinsulator and shows one of the bridgerods in the open position. Figs. 10and 11 are transverse sections taken, respectively, on lines Y Y and Z Zof Fig. 8. plan view of the contact-block and upper row ofcontact-springs. Fig. 13 is a front elevation of the actuating mechanismfor the switch and shows such mechanism in its first position. Fig. 141:is a similar View showing such mechanism in its second position. Fig. 15is a top View of that portion of the actuating mechanism which islocated back of the supporting-stardard. Fig. 16 is a front View showingthe relation of one of the levers to the locks. Fig. 17 is a sideelevation of the actuating mechanism.

Referring to the drawings, Figs. 1, 2,-and 3 illustrate diagrammaticallythe general relation existing between the main distributing system, theoil -switch, and its energizing mechanism. In these figures, A indicatesthe three conductors of a three-phase system; B, oil-wells; O,bridge-rods, each coacting with two oil-wells; 1), source of constantcurrent; E, electromechanical hand=switch, located at a distance fromthe oil-wells; F, contact-arm of hand-switch; G G, actuatingmagnets,'located at the oil-wells, for raising and lowering the bridge-pieces andfor moving the switch-levers H H. In Fig. 1 of the diagram the parts areshown in the position which they would occupy with the bridge-rods ele-Vated and the circuits through the oil-wells broken. It will be observedthatthe contactarm of the hand-switch E at this time occupies amidwayposition and that the switchlever H covers the contacts I of theactuating mechanism located at the right. In Fig. 2 the contact-arm F ofthe hand-switch E is shown asthrown to the left and the switchlevers HH, respectively covering the contacts I 1, atthe right and left of themechanism and that the bridge-rods are half-way in the oil-wells. InFig. 3 the contact-arm is supposed to be thrown to the left, with thecontact-levers H H both thrown to the left and with the contact-lever Hcovering the contacts I, and were this figure extended it would show thebridge-rods as fully inserted within the oil-wells and in electricalcontact Fig. 12 is a with the contact devices contained \tithin theoil-wells.

The operation of the device, so far as relates to the action of thehand-switch upon the actuating mechanism and the actuating mechanismupon the hand-switch, is as follows: Assuming the contact-arm F of thehand-switch E to be thrown to the left? 0., into the position shown inFig. 2a current will flow from dynamo D through conductor J magnet K,magnet Gr, conductor M, contacts I, conductor N back to dynamo. The pullof the solenoid K, acting through its core, will maintain thecontact-arm of the handswitch in the position shown in Fig. 2 until theswitch-levers H H have been pulled by the solenoid (1, acting throughits core 0, to the left-hand position i. 0., into the position shown inFig. 3. As soon as the switch-lever H leaves the contacts on the rightthe circuit will be broken through solenoid K, at which time thecontact-arm of the hand-switch E will, under the action of a suitablespring L, return to its initial positiont'. (1., to that shown inFig. 1. When next it is desired to open the circuit, the hand-switch Eis pulled to the right, which reverses. the operation. In practice Iprefer that the relation of the parts shall be such that the magnets inthe hand-switch shall be deenergized slightly before the movement of theoil-switch, excited by the hand-switch, has been completedv. just beforethe contact is made or broken. I take this course as a measure ofprotection, although I do not consider it essential.

Referring now to the construction of the oil-switch, 1 indicates a vaultor receptacle in which the oil-wells are located. This receptacle, whichis suitably inclosed at the top and bottom, is divided into a series ofchambers l 1 1 by insulating-partitions 2, of brick or other suitablematerial, and is provided on the front with suitable doors 3. I preferto make the doors in two parts secured together at their center by meansof a button 4 or other device, as shown. The doors, however, may beotherwise arranged. Located within each chamber are two oil-wells B. Theconstruction of the oil-wells is best shown in Fig. 8, each of whichconsists of an outer casing 5, with an insulating-lining 6, which may bemade either of liberor of avitreous material, as desired. Situated abovethe lining 6 is a washer 7, and mounted upon the washer is a porcelaininsulator 8, provided with a circumferential supporting-flange 9.Situated over the flange 9 is asecond washer 10,and,finally, over thiswasher a cap or cover 11, secured to the casing 5 by means ofascrew-thread. The supporting-flange of the insulator 8 is provided withthe radial grooves 12 to provide openings through which the oilcontained within the casing when expanded by heat may rise into thecavity of the cap 11 and when the heat has been dissipated flow backagain into the casing or when subjected to a disruptive discharge, owingto the formation of an excessive arc, may be carried entirely out of thecasing. Located within the insulator 8 is a guide-tube 13, securedtherein by means of washers 14. The upper end of the tube 13 has formedon it a screw-thread 15, over which is applied an annular guide-cap 16,which I prefer to make of steel or other refractory material that willnot be worn by the reciprocations of the bridge-rod working through it.In Fig. 9 I have shown the guidecap 16 detached from the guidetube 13and held by means of springs 17, secured to the bridge-rod (J, theobject of which arrangement is to prevent the cap 16 from being lostwhen it is unscrewed from the tube 13 and to permit the removal of anoil-well from a chamber of the vault or receptacle without the necessityof the attendant touching any part of the switch mechanism. Connected tothe bottom of the casing 5 is a base-piece 18, supported in an insulator19, which corresponds in shape to the insulator 8. The basepiece 18 isrecessed on its interior to form an annular threaded chamber 20.Situated within this chamber is an annular ring 21, to which is securedfour pairs of contact-strips 22 23. These strips are formed of goodconducting-material and have flat surfaces, so as to bear upon the sidesof the bridge-rods C, which are made square. The annular ring21 is heldin position by means of the threaded ring 24. Carried at the upper endof the contact-strips 23 are the brass contact-blocks 25, secured inposition by means of screws 26. These blocks may be readily removed byreleasing the screws when it is desired to insert a new contact-block incase one should be injured. In the practical operation of the device thearcing always takes place between the bridge-rod Cand this block, whichthus serves to protect the contact-strips 22 23. Situated below theannular chamber 20 is a second annular chamber 27, within which islocated an annular plate 28. Located below the plate is a helical spring29. The function of the plate and spring is to overcome the frictionexerted by the contact-strips 22 23 on the bridge-rod C, and thusfacilitate the opening of the switch. 30 indicates a conductor securedat one end to the bottom of the oil-well and at the opposite end to oneterminal of a conductor A of the main circuit.

I will now describe the means by which the oil-wells (two for eachconductor) are supported within a chamber of the vault or receptacle andhow these oil-wells may be readily removed from the vault for inspectionand repair.

Located within each one of the receptacles 1" 1" 1 is a platform 31,which platform is carried by four pivoted links Projecting from the backof the platform is a stop 33,

which limits the inward movement of the platform, and projecting upwardfrom the bottom of the receptacle is a stop 34, which limits thedownward and outward movement of the platform. The front of the platformis provided with a pivoted arm 35, Fig. 7, in which is formed an eye 36,Fig. 5. When it is desired to examine the oil-wells B, a hook is caughtin the eye 36 of the pivoted arm 35, and the platform 31 and oil-wellsare drawn forward to the position shown in the dotted lines. which hasbeen found very convenient in practice; but 1 do not wish to limitmyself to the precise construction described, as it will be within theintent of my invention to mount the oil-wells upon any suitable platformor in any suitable manner within the inclosing chambers.

Secured to the lower end of the conductor 30, below the table 31, is apivoted switchblade 37, which is adapted'to coact with the spring-clips38 on the end of a conductor A. The conductor A is shown as mounted inan insulator 39. The switch 37 is not an essential part of my device;but I find it convenient for use after the main contacts in the oilwellshave been separated, as it insures the breaking of the circuit, and thusin a measure gives confidence against accidents to the workman who mustexamine or repair the switch. 1 wish it understood that I do not intendto use this switch in any wise as a means for breaking the main circuitin the ordinary operation of the device. Contact with the oppositeoil-well is made through a contactplate 40, which coacts with clips 41,carried by a conductor A, mounted in the insulator 42. I do not wish tolimit myself in any Wise to the means described for connecting theoilwells to the main circuit-conductors, as other means than those shownmay be employed.

I will now describe the device employed for elevating and lowering thebridge-rods C. Each pair of rods is connected together by means of aconducting cross-head 43, and to each of these cross-heads is connected:1. wooden rod 44, which are united at the top by means of a cross-head45, Fig. 4. This cross-head is connected to a tube 46, which moves on avertical rod 47, forming a part of a standard 50, mounted on top of thevault or receptacle.

It will be understood from the description so far as given that thebridgerodsC and cross-head 43 form, in fact, a bridge between the endsAA of a conductor and that therefore the making and breaking of acircuit traversing a conductor of a system is wholly within one chamberof the receptacle, and,

further, that if simultaneous movement is given to all of thebridge-rods the making and breaking of all of the circuits (in thepresent case three) will occur at the same time.

Arranged transversely of the standard 50 is a shaft 51, Fig. 17, and onthe inner end of The arrangement described is one this shaft is looselypivoted a lever 52. The lever 52 is connected through the pivoted link53 with the cross-head 45. Thus it will be seen that when the lever 52is rotated the cross-head will be elevated or depressed in accordancewith the movement of the lever. Mounted upon the other end of the shaft51 and occupying a position at one hundred and eighty degrees from thatoccupied by the lever 52 is a lever 54. Secured at one end to this leverand on the other end to the frame is a helical spring 55, the object ofwhich arrangement is to counterbalance the weight of the lever 52, link53, cross-head 45, rods 44, cross-head 43, and bridge-rods (J, and thuspromote ease of movement of the parts. Figs. 5 and 17 respectively showthe position of the parts when the switch is closed and open. Mountedalso upon the shaft 51 is a lever 56. This lever is fixed to the shaft51 and is provided with a pair of rearwardly-extending arms 57, whichembrace the lever 52. The arms 57 of the lever 56 are separated for adistance somewhat greater than the width of the lever 52. Consequentlywhen the lever 56 is set in motion the arms 57 will impart to the lever52, which is loose on the shaft 51, first, a hammerblow, then acontinuous push, until the limit of the travel of the lever 56 has beenreached. The lever 52 is permitted to travel through one hundred andeighty degrees and the lever 56 through a slightly-greater distance,whenfur ther motion will be arrested by reason of the spring-stops 58projecting from the frame 50. Mounted also upon the shaft 51 is abandwheel 59, and secured to this wheel is a band 60. The band may besecured by means of a screw 61 or otherwise. All that is required isthat the band shall be so fastened as not to slip upon the wheel. ofband are the cores O O of the solenoids G Gr. Situated under eachsolenoid is a dashpot 62, which may be of any suitable construction.

piston 64, located between metallic disks 65. These disks are connectedthrough the rods 66 with a plate 67, in which is an opening 68 for therod 69. The rod 69 is connected to the bottom of a core and issurrounded by a sleeve 70. Located on the rod 69 is a nut 71, thepurpose of which is to determine by moving this nut up along the rod 69the moment when the dash-pot shall be thrown into operation in theupward movement of the core. The dash-pot is thrown into operation onthe downward movement of the core by the end of the sleeve 70 strikingthe plate 67.

72 represents a valve in the dash-pot, which in the present caseconsists of a ball and suitable seat. This arrangement of ball and seatprevents the entrance of air in the upward movement of the piston, butpermits the en trance 'of air on the downward movement of Preferably,however, the dash-pot consists of a casing 63, in which is a leatherConnected to the ends the piston. The chief object of the dash-pot is tocushion the movement of the operating parts of the switch-actuatingmechanism.

On the end of the rod 69 is an eye 73, by means of which an operatorwith a hook may open the switch from the outside of the receptacle.

I will now describe the mechanism by reason of which theactuating-solenoid, as also the solenoid which at the time controls thehandswitch, are deenergized justbefore the switch mechanism hascompleted its movement of one hundred and eighty degrees, or, in otherwords, just before the switch mechanism has closed the circuit throughthe switch or opened the circuits through the switch.

Located on the shaft 51 and back of the band-wheel 59 or forming a partof the bandwheel is a cam-wheel 80, having formed in its rear surface acam-slot 81. This slot is open at the center 82 and communicates withthe periphery of the cam-wheel and is normally closed at the ends by thesprings 83, which are secured to the body of the camwheel at 84 and arefree to be moved outward at 85. The cam-wheel 80 moves coincidently withthe wheel 59. Coacting with the camwheel 80 are the pivoted levers H H,respectively carrying the projecting pins 86 86. In Fig. 13 the pin 86is shown as resting upon the eccentric surface of the cam-slot and thepin 86 upon the periphery of the cam-wheel. Mounted upon the upper endof the levers H H are the bridge-pieces 87 87. These bridgepieces arearranged to bridge the contacts I I. In Figs. 1, 2, and 3 the variouspositions which the levers H H will take upon the rotation of thecam-wheel will be seen. In Fig. 1 the pin 86 is in the cam-slot andbears upon the eccentric surface of the cam-slot, and the pin 86 islocated external to the cam-wheel and bears upon its periphery. In Fig.2 the pins 86 86 both bear upon the periphery of the cam-wheel, the pin86, owing to the rotation of the cam to the left, having moved out ofthe cam-slot and its movement raised the upper spring 83 and passed outfrom under the spring. In Fig. 3 the pin 86 has dropped into thecam-slot through the opening 82 and bears upon the eccentric surface ofthe camslot and the pin 86 is external to the camwheel and bears uponits periphery. The position of the pins 86 86 relative to the camwheeland cam-slot, as described, are those which take place when thecam-wheel is rotated to the left. Corresponding positions in reverseorder will be taken by such pins when the cam-wheel is moved to theright.

In order to prevent the possible operation of the switch by means of ajar, I provide means for locking the levers 56 52. Projecting forwardlyfrom the lever 52 is a pin 88, and situated on the back of thesupportingplate 89 is a pivoted latch 90. Over the rear end of the latchis a stop 91 and over the front end a spring 92. The forward end of thislatch is provided with a projecting pin 93, which coacts with the lever56. A corresponding latch 94 is shown in the bottom of Fig. 13.

95 represents buffers in the path of movement of the levers H H; 96, aspring which connects the levers H H.

The operation of this portion of the device is as follows: When acurrent is sent through one or the other of the magnets G G, a core 0 isattracted. The movement-of the core transmitted to the band rotates theshaft 51. This movement is transmitted to the lever 56, which moving itstop cam-surface under the pin 93 of the latch 90 raises the latch out ofthe path of movement of the pin 88 on the lever 52. The lever 56 thenimparts a blow to the lever 52 and pushes it continuously forward and.to the left until both levers have traversed one hundred and eightydegrees, at which point the pin 88 is caught by the latch 94 and thelevers H H will have moved to the position shown in Fig. 3 of thedrawings.

I wish it understood that I do not limit my self to the specificmechanism described for altering the circuit connections to theactuating solenoids or the solenoids at the handswitch, as many changesmay be made in this portion of the apparatus without departing from theintent of my invention.

Having thus described my invention, I claim 1. An electric switch,comprising an insulated chamber, a pivoted platform in said chamber, andan oil-well mounted on the platform.

2. An electric switch comprising an insulated chamber, a pivotedplatform, an insulator mounted on the platform, and an oil-well mountedon the insulator.

3. An electric switch, comprising in its construction an insulatedchamber, a pivoted plu tform, an oil-well mounted on said platform, andmeans for connecting said oil-well to the terminals of an electricalconductor.

1. An electric switch comprising in its construction an insulatedchamber, a pair of insulated terminals projecting into said chamber, apivoted platform, a pair of oil-wells mounted on said platform, andmeans for establishing electrical connection between the oil-wells andthe terminals.

5. An electric switch, comprising in its construction an insulatedchamber, a pair of insulated terminals projecting into said chamber,spring-clips on the end of said terminals, a pivoted platform, a pair ofoil-wells mounted on said platform, and mechanism connected to theoil-wells for establishing electrical connection between the oil-wellsand the terminals.

6. An electric switch comprising in its construction an insulatedchamber, a platform,

pivoted links introduced between such platform and chamber, and apivoted eye connected to said platform.

7. An electric switch comprising in its construction, a vault orreceptacle divided into a number of separated and insulated chambers, apivoted platform in each chamber, and mechanism for making and breakingcircuits mounted on said platform.

8. An electric switch comprising in its construction, a vault orreceptacle divided into a number of separated and insulated chambers, apivoted platform in each chamber, and a pair of oil-wells mounted oneach platform.

9. An electric switch comprising in its construction, a vault orreceptacle divided into a number of separated and insulated chambers, apivoted platform in each chamber, a pair of oil-wells mounted on eachplatform, and means for connecting said oil-wells tothe terminals of anelectrical conductor.

1.0. An electric switch comprising in its construction, a vault orreceptacle divided intoa number of separated and insulated chambers, apivoted platform in each chamber, a pair of oil-Wells mounted on eachplatform, means for connecting one oil-well of a pair with one terminalof a conductor, and a line-switch interposed between the other oil-wellof the pair and the other terminal of the conductor.

11. An electric switch comprising in its construction, an oil-wellhavingan inclosing casing, an insulating-lining, an insulator havingopenings in its body mounted in the top of the casing, an annular caplocated over the insulator, a series of spring-contacts mounted in thelower portion of the casing, and contactblocks carried by saidspring-contacts.

12. An electric switch comprising in its construction, an oil-wellhaving an inclosing casing, an insulating-lining, an insulator providedwith a supporting flange having openings therein mounted in the top ofthe casing, a guide-tube carried by said insulator, a series ofspring-contacts mounted in the lower portion of the casing, contactblocks carried by said spring-contacts, and a reciprocating bridge-rodcoacting with said spring-contacts and contact-blocks.

13. An electric switch, comprising in its construction an oil-wellhaving an inclosed casing, an insulating-lining, an insulator providedwith a flange having openings therein mounted in the top ofthe casing, aguide-tube carried by the insulator, aguide-cap mounted on theguide-tube, a series of spring-contacts located in the lower portion ofthe casing, contact-blocks carried by said spring-contacts, and areciprocating bridge-rod adapted to coact with said spring-contacts andcontact-blocks.

14. An electric switch comprising in its construction an oil-well havingan inclosing casing, a series of spring-contacts mounted in the lowerportion of the casing, a reciproeating bridge-rod which coacts with saidcontacts, and a spring-pressed plate which coacts with said bridge-rodto overcome the friction of the spring-contacts.

15. An electric switch comprising in its construction an oil-well, aguide-cap mounted on the top of the oil-well, a reciprocatingbridgerod,a pair of springs carried by said bridgerod and adapted to coact withsaid guide-cap when it is removed from the oil-well.

16. An electric switch comprising in its construction, a vault orreceptacle divided into a number of separated and insulated chambers, apivoted platform in each chamber, a pair of oil-Wells carried oninsulators on each platform, and a pivoted link connected to eachplatform by means of which the platforms may be drawn out of thechambers.

17. An electric switch comprising in its construction, avault orreceptacle divided into a number of separated and insulated chambers, apivoted platform in each chamber, a pair of oil-wells carried oninsulators on each platform, a pivoted link connected to each platformby means of which the platforms may be drawn out of the chambers, andmeans for limiting the inward and outward movement of the platforms.

18. In combination with the bridging devices of an oil-switch, means forimparting motion to said bridging devices, said means consisting of apair of solenoidal magnets, a horizontally-disposed shaft adapted to berotated in one direction or the other as one or the other of the magnetsis energized, means for shifting the path for the current through saidsolenoids, and means for shifting the position of thecurrent-controlling device froln an operative to a neutral position whenthe movement of the bridging devices in either direction to open orclose the switch has been reached.

19. In combination with the bridging device of an oil-switch, of meansfor imparting motion to said bridging device, said means consisting of apair of solenoidal magnets, a horizontally-disposed shaft adapted to berotated in one direction or the other as one or the other of the magnetsis energized, a lever carried by said shaft, a second lever connected tothe bridging device and adapted to be struck a hammer-blow and rotatedin one direction or the other when the first-named lever is moved.

20. In combination with the actuating mechanism for the bridging devicesof an oil-switch, an independent source of energy, a hand-operatedswitch, solenoids which serve to hold the switch in fixed positionsuntil deenergized, and means operated by the actuating mechanism fordeenergizing the solenoids of the hand-switch.

21. In combination with the actuating mechanism for the bridging deviceof an oil-switch, an independent source of energy, ahandswitch,solenoids which serve to hold the switch in fixed positionsuntil deenergized, and a pair of levers moved by the actuating mechanismand which will alternately break and close circuits through thesolenoids of the hand-switch.

22. In combination with the bridging devices of an oil-switch, means forcounterbalancing the weight of the bridging devices, means forreciprocating the bridging devices, and means for imparting to thereciprocating means a hammer-blow when starting, to overcome the inertiaand frictional resistance of the bridging devices against movement.

23. In combination with the bridging devices of an oil-switch, ofactuating mechanism therefor, said actuating mechanism consisting of ahorizontal shaft, a band-wheel on the end of the shaft, a band over saidband-wheel, a pair of magnets having their cores attached to the ends ofthe band, a lever attached to said shaft, and a second lever loosely pixoted on said shaft and connected to the bridging devices.

24. In an oil-switch and in combination with the mechanism forreciprocating the bridging devices of said switch, a horizontal shaft towhich motion is imparted alternately in opposite directions by a pair ofmagnets, a camwheel mounted on said shaft, a pair of levers adapted tocoact with said cam-wheel, and contacts in circuit with a source ofenergy adapted to be bridged by the said levers.

25. In combination with the actuating mechanism for the bridging devicesof an oilswitch, of means for limiting the movement of said actuatingmechanism after the determined range of movement has been ended, suchmeans consisting of latches adapted to coact with the lever which raisesand lowers the bridging devices and with the lever which impartsmovement to such first-named lever.

26. In combination with the actuating mechanism for the bridging devicesof an oilswitch, a cam-wheel having a cam-slot formed in one face, andmeans consisting of lovers having projecting pins which coact with saidcam-slot to alternately reverse the circuit con nections to theactuating mechanism.

27. In combination with the mechanism for reciprocating the bridgingdevices of an oilswitch, a horizontal shaft, means for prod ucingrotative movement of said shaft alternately in opposite directions, acam-wheel mounted on said shaft, said cam-wheel provided with a cam-slotopen at the center and covered at the ends by a pair of springs, a pairof levers provided with pins which move in said cam-slot, and bridgingcontacts carried by said levers and adapted when the cam is rotated toalternately close and open circuits through said means for producingrotative movement of the shaft.

In testimony whereof I afiix my signature in the presence of twowitnesses.

HENRY PRICE BALL.

Witnesses:

J. E. PEARSON, U. E. S'ruonnn.

